AWK script to atomically update IPSet based on ripe.net datebase

china.awk

#!/usr/bin/awk -f
BEGIN {
	FS="|";
        print "create china_new hash:net" | "ipset restore"
}
$2 == "CN" && $3 == "ipv4" {
    prefix=32;
    while ($5 > 1) {
        --prefix;
        $5 = $5/2;
    }
    print "add china_new " $4 "/" prefix | "ipset restore"
}
END {
    print "swap china_new china" | "ipset restore"
    print "destroy china_new" | "ipset restore"
}